On Mon, Dec 26, 2022 at 10:29 AM Edoardo Centofanti < edoardo.centofant...@universitadipavia.it> wrote:
> Thank you for your answer. Can you provide me the full path of the example > you have in mind? The one I found does not seem to exploit the algebraic > multigrid, but just the geometric one. > cd $PETSC_DIR/src/snes/tutorials/ex5 ./ex5 -da_grid_x 64 -da_grid_y 64 -mms 3 -pc_type gang and for GPUs I think you need the options to move things over -dm_vec_type cuda -dm_mat_type aijcusparse Thanks, Matt > Thanks, > Edoardo > > Il giorno lun 26 dic 2022 alle ore 15:39 Matthew Knepley < > knep...@gmail.com> ha scritto: > >> On Mon, Dec 26, 2022 at 4:41 AM Edoardo Centofanti < >> edoardo.centofant...@universitadipavia.it> wrote: >> >>> Hi PETSc Users, >>> >>> I am experimenting some issues with the GAMG precondtioner when used >>> with GPU. >>> In particular, it seems to go out of memory very easily (around 5000 >>> dofs are enough to make it throw the "[0]PETSC ERROR: cuda error 2 >>> (cudaErrorMemoryAllocation) : out of memory" error). >>> I have these issues both with single and multiple GPUs (on the same or >>> on different nodes). The exact same problems work like a charm with HYPRE >>> BoomerAMG on GPUs. >>> With both preconditioners I exploit the device acceleration by giving >>> the usual command line options "-dm_vec_type cuda" and "-dm_mat_type >>> aijcusparse" (I am working with structured meshes). My PETSc version is >>> 3.17. >>> >>> Is this a known issue of the GAMG preconditioner? >>> >> >> No. Can you get it to do this with a PETSc example? Say SNES ex5? >> >> Thanks, >> >> Matt >> >> >>> Thank you in advance, >>> Edoardo >>> >> >> >> -- >> What most experimenters take for granted before they begin their >> experiments is infinitely more interesting than any results to which their >> experiments lead. >> -- Norbert Wiener >> >> https://www.cse.buffalo.edu/~knepley/ >> <http://www.cse.buffalo.edu/~knepley/> >> > -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener https://www.cse.buffalo.edu/~knepley/ <http://www.cse.buffalo.edu/~knepley/>